PURPOSE: A crank shaft measuring device is provided to simplify a task for setting a crank shaft and to improve working efficiency by remarkably reducing time for measurement. CONSTITUTION: A crank shaft measuring device comprises a surface plate(10), a slide rail(15), support blocks(20), and a measuring member(50). The surface plate has a predetermined area. The slide rail is installed along the circumference of the surface plate at constant depth. The support blocks are installed separately in the surface plate to be faced each other for supporting both ends of a crank shaft(100). The measuring member measures the crank shaft while moving along the slide rail.
